1. Field of the Invention
The present invention relates to a method for taking up the amorphous ribbon, which was quickly cooled and solidified from molten metal by means of a cooling roll and was shaped, and an apparatus therefor.
2. Description of the Prior Art
The amorphous ribbon is shaped at a rate of 20 to 40 m/sec. to have a width of 5 to 25 mm and a thickness of 10 to 30 .mu.m. This ribbon is generally called the "narrow ribbon" and is seriously fragile to shocks or torsions. The leading end of the ribbon, that was shaped at first, has an ununiform section and is disused, and this disused portion has an unfixed path of fly from the roll. The normal portion to be used and to come after the disused portion has such a large amplitude in the path of fly that it pulsates. This makes it difficult to take up the ribbon while the same is being shaped. Since, however, it omits or spares the time periods for the subsequent steps to take up the ribbon immediately shaped, there have been conceived and disclosed a number of take-up methods and apparatus therefor.
In Japanese Patent Publication No. 56-99054, a suction port, a guide tube and take-up means are arranged in the recited order so that the ribbon may be guided by a gas flow having a higher velocity than its shaping rate. Concerning the take-up means, the guidance to the take-up position and the combination of components, however, there is no substantial disclosure for practicing the method or apparatus. Especially, the disused portion of the ribbon will go out of control and will fly at first to induce troubles such as the clogging, breakage and/or disordered take-up, but there is no disclosure on the means for solving those troubles. In short, the means before and after the instant, at which the ribbon is brought into contact with the drum, are the most important for satisfying the take-up. In Japanese Patent Publication No. 56-28166, on the other hand, the rotational speed of the take-up reel is made smaller by about 2% than that of the cooling surface of the roll, so that no substantial tension is applied to the ribbon. In the foregoing Japanese Patent Publication No. 56-99054, on the contrary, a tension is applied to the ribbon, but no substantially effective disclosure is made on the flow velocity.
The guidance into the drum by sucking the ribbon is disclosed in Japanese Patent Publication Nos. 62-127145 and 62-151251. According to these two, the flown ribbon is sucked directly to a sucker till it is guided to the vicinity of the drum. If the flown ribbon is thus directly sucked and guided, the shocks due to the fly pulsations of the ribbon and the guiding shocks for correcting the path of the ribbon are involved. That is, if the flying ribbon is directly captured so that it may be corrected in the flying direction, the shocks are multiplied to break the ribbon.
In Japanese Patent Publication No. 63-72451, the ribbon is tensed after it has passed through a guide groove by means of a clamping roller, and the guide groove is then taken away to push the tensed ribbon onto the drum. Since the guide groove is provided to capture the ribbon on the roller to push it onto the drum, serious shocks are caused when the pusher comes into contact with the ribbon. The ribbon would be broken unless it is effected tension and movement without any contact.
The drum for taking up the ribbon is disclosed in Japanese Patent Publication No. Hei 01-17785. Here the drum which can swing in the vicinity of the roll is equipped with a magnet or suction port and is given a lower circumferential velocity than that of the roll so that it may take up the ribbon directly from the roll. The purpose to form the drum to be able to swing is not to make the drum come into contact with the ribbon but to adjust the winding diameter of the ribbon. In Japanese Patent Publication No. 59-94525, there is disclosed another drum which has an adhesive and which can swing.
The substantial take-up of the ribbon involves a variety of components, and it is very difficult to determine the individual objects and structures of the components and the positions and order of the components to set. There has been no substantially practical disclosure on the order of components in relation to the running of the ribbon, and the relation and timing of operations of the components, namely, to deal with the disused portion of the ribbon, to fix the path of the flying ribbon without imparting the shocks to the ribbon, to cause the drum to contact with the ribbon thereby to start the taking-up. According to Japanese Patent Publication No. 63-30264, the ribbon is guided by means of moving clamp rollers and is wound on the drum. This disclosure has many factors for breaking the ribbon because of the rotational speed and moving velocity of the clamp rollers which are adjusted to the shaping rate of the ribbon, because the ribbon is guided with contact, and because the ribbon is tensely supported at a large interval.
The ribbon is shaped at a high rate and gets seriously fragile, and its leading end shaped at first has an ununiform section, so that its flying path is unfixed to have a large amplitude. This in turn adversely affects the guidance and the winding. The reliable guidance and cutting of the disused portion has to be satisfied compatibly with the prevention of the normal portion from being undesirably broken. Thus, it is necessary to solve the contradiction between the correct cutting and the undesirable breakage while the ribbon is being moved continuously at a high speed. As has been described hereinbefore, however, there is no consistent disclosure on the guidance of the ribbon out of contact, the dealing of the disused portion, the order of bringing the drum into contact with the ribbon, and so on.